An analysis of the long run effects of economic growth, urbanization & population density on transport emissions in Nigeria: A bounds testing approach

Abstract

Global concern on environmental quality and human existence demands cutting down the emissions of carbon dioxide (CO2) from all affiliate productive sectors. Empirical identification of the emissions drivers is pre-requisite for its effective mitigation. Transport sector as one of the highest CO2 emitting sectors over a decade in Nigeria received scanty empirical investigation. The study empirically assessed the long run nexus among transport CO2 with economic growth, urbanization as well as rural population over the period 1971 to 2018 for informed mitigation strategies. The paper used the ARDL bounds testing co-integration approach, Dynamic Ordinary Least Square (DOLS) as a robustness check in addition to the pre and post estimation diagnostics tests, it adopt theoretical Stochastic Impact by Regression on Population Affluence and Technology (STIRPAT). In satisfying the ARDL condition, none of the series is co-integrated of order two and there exists a long run equilibrium relationship with correct sign of speed of adjustment (ECM). In the long run, Economic growth, Urbanization, population density and rural population have significant positive effects on transport carbon emissions in Nigeria. The paper recommends the need for the adoption of fuel efficient and environmentally friendly transport system, improvement of the transport infrastructures and subsidized public transport by government. Relocation of some government institution that help in reducing rural urban movement that trigger increase in transport energy demand and emissions is another policy option. There is need for further studies to incorporate other transport related variables like transport energy consumption, transport intensity, and panel-based analysis among others.